We came back Sunday evening from a quick unexpected family visit in Mexico and in one of the tanks I found a disaster. All the fish but 2 micro danios and the male gudgeon had survived the massacre.

Probable reason: apparently there was a power outage and the HOB didn't start back up. And even the plants in my tank didn't help. This is a divided tank and the other side wasn't affected reinforcing my idea that it was the HOB.

The person feeding the fish probably hadn't seen it and even so, wouldn't have known what to do. So, i have decided that these HOBs are going to be replaced.

I am currently looking into the matten filters again or otherwise sponge filters for the smaller tanks.

That is terrible news. But one of the many reasons why I use the suction cup type sponge filters. There cheap, easy to maintain, easy to clean, perfect for small tanks and always come back on with the air pump after a power outage.

I have to say I am not feeling the love from mine as of late either, I had one half empty a 55G tank onto the floor of my office last year. Not to mention the "I don't want to restart after a power outage" problem.

Been real tempted to put on my DIY hat and come up with a canister filter out of a 5gal bucket for some time now, maybe next winter.

Sorry for the loss Biulu, it's never a fun day when this type of thing happens.